FSMC notes (for maple native)
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There is an application note for all this which is helpful; see the ST website.

Chip details
    IS62WV51216BLL
    512k x 16
    19 address input
    16 data inputs

For simple debugging, i'm going to set all the access parameters to maximum
time values (aka, slowest). I'm going to use not-extended mode 1 for
read/write.

Steps from application note:

- enable bank3: BCR3_MBKEN = '1'
- memory type is SRAM: BCR3_MTYP = '00'
- databuse weidth is 16bits: BCR3_MWID = '01'
- memory is nonmultiplexed: BCR3_MEXEN is reset (= '0')
- everything else is cleared

Parameters:

 t_wc (write cycle) = 55ns
 t_rc (write cycle) = 55ns
 t_pwe1 (write enable low pulse) = 40ns
 t_aa (address access) = 55ns

So address setup (ADDSET) = 0x0, data setup (DATAST) = 0x3

Using bank1, NOR/PSRAM1 memory starts at 0x60000000.

Oops, obviously have to turn on the clock for all those GPIO pins...

Not-super-helpful-link:
http://www.keil.com/support/man/docs/mcbstm32e/mcbstm32e_to_xmemory.htm

PG9 (which is NE2) is twiddling on reset?